1. Field of the Invention
The present invention relates to a pot with a multi-layered bottom and a manufacturing process thereof, and more particularly, to a pot with a multi-layered bottom which can cook foods uniformly in a short time with increased heat efficiency and heat conductivity and which is aesthetically pleasing and a manufacturing process thereof.
2. Description of the Related Art
Generally, cookware used for cooking foods is made of stainless steel. However, such conventional cookware is problematic in that its base bottom may be not uniformly heated and heat efficiency may be reduced. Thus, three-layered clad metal cookware has been proposed.
A clad metal is a composite plate material consisting of a stainless steel-clad aluminum plate, or an aluminum plate clad with a stainless steel plate, and also a material formed by integrating two or more different metal plates. It is used for kitchenware, motor parts, high speed subway and railway parts, aircraft materials, sound proof equipment materials, building materials, etc.
In the kitchenware art, the clad metal has a high degree of heat conductivity and heat conservativity due to the aluminum and a high degree of corrosion resistance due to the stainless steel, and it is aesthetically pleasing
However, in using the cookware (hereinafter, xe2x80x98clad metal cookwarexe2x80x99) with a three-layered bottom using the clad metal, a high degree of heat efficiency and heat conductivity is required for cooking food rapidly and heating it uniformly.
Due to this, a structure is considered in which the aluminum of the clad metal cookware is clad with copper which has a higher degree of heat conductivity than the aluminum. However, since the aluminum and the copper are nonferrous metal, it is difficult to clad them together the process of which will now be described in more detail.
Firstly, in a process of heating the clad metal cookware at a temperature slightly lower than the melting point of aluminum in order to clad the clad metal cookware with the aluminum, the copper, with a thickness less than the aluminum, melts earlier, so it is difficult to adjust preheating conditions.
In addition, in the heating process, an oxide coating is generated on the surface of the copper, thus reducing the adhesion force to the aluminum.
Meanwhile, because the base bottom of the conventional clad metal cookware is made of aluminum and stainless steel, the color of the product becomes a single, silver white color, thus making the product look relatively simple.
It is therefore, an object of the present invention to provide a pot with a multi-layered bottom which can cook foods in a short time with increased heat efficiency and heat conductivity by firmly cladding materials with high heat conductivity such as copper with aluminum and which has a pleasing appearance and a manufacturing process thereof.
To achieve the above object, there is provided a pot with a multi-layered bottom made of a stack of different materials in accordance with the present invention, characterized in that the pot A pot with a multi-layered bottom made of a stack of different materials, the pot comprises: an upper aluminum plate being fixed to the bottom of the pot in contact with each other; a perforated plate being fixed to the lower side of the upper aluminum plate and having a plurality of hollow portions; a lower aluminum plate being fixed to the lower side of the perforated plate; and a stainless steel plate being fixed to the lower side of the lower aluminum plate; wherein the upper aluminum plate and lower aluminum plate are interconnected with each other through the hollow portions of the perforated plate by a pressure.
Preferably, the perforated plate is made of at least one material selected from the group consisting of copper, brass, gold and silver.
In addition, the stainless steel plate is provided with a communicating portion thereto a clad member being inserted and fixed.
Further, there is provided a manufacturing process of a pot with a multi-layered bottom in accordance with one embodiment of the present invention, comprising: preparing a perforated plate, a stainless steel plate, an upper aluminum pate, a lower aluminum plate and a clad member into a size corresponding to the bottom of the pot; cutting the perforated plate, the stainless steel plate and the upper and the lower aluminum plates so that they have a predetermined height; washing the perforated plate, the stainless steel plate and the upper and the lower aluminum plates in order to remove oiliness and impurities thereon; forming a plurality of hollow portions in the perforated plate and forming a communicating portion in the stainless steel plate; fixing the upper aluminum plate to the upper side of the perforated plate by spot-welding; spot-welding the lower aluminum plate to the upper side of the stainless steel plate and spot-welding the clad member to the position corresponding to the communication portion of the stainless steel plate at the lower side of the spot-welded aluminum plate; spot-welding the upper aluminum plate to the bottom of the pot and then the lower aluminum plate to the perforated plate one after another; preheating the bottom of the pot temporally assembled; cladding the plates in their stacking order by pressing the bottom of preheated pot, thereby interconnecting the upper aluminum plate at the upper side of the perforated plate and the lower aluminum plate at the lower side of the perforated plate through the hollow portions of the perforated plate; polishing the outer surfaces of the pot in order to make them glossy.
In addition, there is provided another manufacturing process of a pot with a multi-layered bottom in accordance with one embodiment of the present invention, comprising: preparing a perforated plate, a stainless steel plate, an upper aluminum plate, a lower aluminum plate and a clad member into a size corresponding to the bottom of the pot; cutting the perforated plate, the stainless steel plate, the upper aluminum plate and the lower aluminum plate so that they have a predetermined height; washing the perforated plate, the stainless steel plate, the upper aluminum plate and the lower aluminum plate in order to remove oiliness and impurities thereon; forming a communicating portion on the stainless steel plate; stacking the upper aluminum plate, the perforated plate, the lower aluminum plate, the stainless steel plate and the clad member one after another on the bottom of the pot and depositing flux between these plates; fixing each of the plates on the bottom of the pot in the stacking order by heating the bottom of the pot and melting the flux; polishing the outer surfaces of the pot in order to make them glossy.
In accordance with the pot with a multi-layered bottom of the present invention, heat efficiency and heat conductivity are improved this cooking food in a short time. In addition, in a case that the perforated plate is made of a colored material, the product has a more pleasing appearance.